Fever and Night Sweats

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Fever and Night Sweats

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Fever is a common sign that on its own is usually little help in making a diagnosis. Persistent high fever needs urgent treatment. Fever over 42.2°C (108°F) produces unconsciousness and leads to permanent brain damage if sustained. Fever can be classified as:

Low: 37.2°-38°C (99°-100.4°F).

Moderate: 38.1°-40°C (100.5°-104°F).

High: >40°C (104°F).

Fever may also be described as:

Remitting - the most common type with daily temperatures fluctuating above the normal range.

Intermittent - daily temperature drops into the normal range and then rises back above normal. If temperature fluctuates widely causing chills and sweating, it is called a hectic fever.

Sustained - persistent raised temperature with little fluctuation.

Relapsing - alternating feverish and afebrile periods.

Undulant - gradual increase in temperature, which stays high for a few days then gradually reduces.

Fever may also be described in terms of its duration; brief (<3 weeks), or prolonged. The term pyrexia of unknown origin (PUO) is used to describe a condition where no underlying cause can be found[1].

Night sweats are common and there is a long list of possible causes, mostly benign but important to diagnose in order to manage effectively. Serious causes of night sweats can usually be excluded by a thorough history, examination and simple investigations if required.

Causes of fever include

Infection: bacterial, viral or fungal. The origin of infection may be obvious or may require careful assessment for diagnosis - eg, infective endocarditis, tuberculosis or other occult long-term infection.

Night sweats

Night sweats are usually defined as episodes of significant night-time sweating that soak the bedclothes or bedding. This is a fairly common symptom.

Although uncomfortable, night-time sweating typically isn't a sign of a serious underlying medical condition. It may be triggered by something as simple as too warm a room or too many blankets on the bed.

Management

The most important aspect of management is the identification and appropriate management of the underlying cause. However, in the case of self-limiting viral infections, the only management required is advice and reassurance.

Do not prescribe oral antibiotics to a child with fever without apparent source[2].

If meningococcal disease is suspected, give parenteral antibiotics at the earliest opportunity (either benzylpenicillin or a third-generation cephalosporin)[2].

Immediate hospital treatment of a child with a very high fever

Give oxygen if there are signs of shock, oxygen saturation of less than 92%, or as clinically indicated.

Simple explanations for patients and their relatives

Drink lots of fluid.

Do not wear too many clothes (do not overdress or underdress) or use too many blankets.

Keep the room at a comfortable temperature but make sure that fresh air is circulating (use a fan if available).

A damp vest and a fan can be effective in lowering temperature.

Don't wipe the sweat off immediately as this helps to cool the body.

Cool baths and tepid sponging are not recommended.

Antipyretic drugs

There is evidence that host defence mechanisms are enhanced by a raised temperature.

Fever is the normal response of the body to infection and unless the child becomes distressed or symptomatic, fever alone should not be routinely treated[3].

Antipyretics (eg, paracetamol and ibuprofen) should therefore not be used routinely but can be of value, especially for patients with systemic disease (particularly heart failure or respiratory failure) and when fever causes acute confusion.

Consider either paracetamol or ibuprofen as an option if a child appears distressed or is unwell.

Do not administer paracetamol and ibuprofen at the same time but consider using the alternative agent if there is insufficient response to the first drug[2].

There is some evidence that both alternating and combined antipyretic therapy may be more effective at reducing temperatures than monotherapy alone. However, there is insufficient evidence to know which of combined or alternating therapy might be more beneficial[3].

Antipyretic agents do not prevent febrile convulsions in young children and should not be used specifically for this purpose[2].

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